Although it sounds like a good idea we can assure you the cons heavily outweigh the pros.
Reshingle roof over old shingles.
Your existing layer of roof shingles is deteriorating and you need to get a new roof installed.
Installation is easier than for a tear off job because you can use the existing shingles as guides for laying the new ones.
The third layer of shingles will be too heavy to be supported.
All shingle manufacturers honor the warranty whether their products are used for a reroof or a new roof.
Has the same manufacturer s warranty.
Installing new roof shingles over old effectively doubles the weight of the roofing so you have to make sure your roof structure can handle the extra load.
If the job is done correctly with the new layer of shingles laid flat over the existing shingles the old roof cushions the new one and serves as a secondary barrier should wind or water ever break through the new shingles.
Remove all of the shingles on the roof.
You want to be sure that you will be installing the shingles over only one other layer though.
Roofing second layer of shingles roofing.
When contemplating a new roof many people hope to simply do a shingle over and avoid the extra cost and mess of tearing off the existing roof and starting from scratch.
If conditions are right new shingles laid over old shingles can be just as attractive and durable as shingles laid on bare sheathing.
The nails in the shingle should come up with the shingle when you pry it off.
One question you might have is can i reroof over existing shingles the answer is it depends state regulations and the condition of your roof both play a role in determining if you need a roof replacement tear off vs cover over.
That s also why building codes commonly limit re roofing to no more than two layers.
Place a pitchfork flat garden shovel or shingle scraper under the shingle.
How to shingle over existing shingles and how to shingle a roof how to install roof shingles shingle layout lines h.
In fact the only pro to a shingle over is it s cheaper and cleaner.
As long as it s done right and under the right conditions installing new shingles over old ones can last as long and look just as good as a complete re roof.
If you are looking to save time installing new shingles over old shingles is a possible roof replacement solution.
Pry the shingle from the roof.